I would try not to worry too much Caseylee. At the end of the day you've got to do what you can, when you can. I've taken on an extra plot this year and i'm still way behind with my digging. I've got stuff queueing up to be put in. i think it's the time of year when many people, myself included, get just a little bit panicky about trying to get everything in, on time.
I can see where you're coming from re the soil being a bit too wet. My clay soil tends to be too wet to dig comfortably for most of the year, then, you get a little honeymoon period between about now and the middle of June, before the uncultivated soil starts to set like concrete and the weather's too hot for serious digging sessions anyway.
I know it's not too popular with the 'Allotment Police', but, i'd just concentrate on doing one small section at a time, without being too fussy, get something in thats relatively 'easy' like broad beans or some early spuds, then move on to the next section. If you dont manage to get the whole plot sorted there's always next year.
As for breaking up large clumps of soil. One tool that i've found quite useful is my Chillington Digging hoe. They dont do a big range for the British market. I've got three of them. I mainly use the Heavy duty digging hoe and the digging fork. I've found them pretty good for smashing up the big clods of soil. All their tools are very reasonably priced and they are a very friendly, helpful bunch of people, as you would expect from a company which has been in business for over a hundred years. You should be able to find them if you do a search on the internet. If you give them a ring they will help you out.
Best of Luck anyway-Marky.B. :)